I have an early build Magnum 06-04 so I need to get my Transmission calibration updated to utilize all of the features of the tuner. I am running the 91 tune and have raised the top speed limiter to 149mph. Not that I'm gonna get there any time soon, but if the need arises I will be able to.
So far I like it, but can't wait to get the trans updated, so I can really play.